The present invention relates to a liquid filling nozzle for use in filling a liquid, such as flowable food, into containers.
Generally, filling nozzles are usually free of any problem for free-flowing liquids such as milk but encounter difficulty in handling at a high speed liquids, such as fresh cream and yoghurt, which are low in flowability since such a liquid is not dischargeable from the nozzle quickly and can not be cut sharp, whereas the present applicant has already proposed a nozzle by which even a liquid of low flowability can be filled into containers at a high speed free of trouble like free-flowing liquids. As disclosed in Examined Japanese Patent Publication No. SHO 59-26550, the proposed nozzle comprises a tubular nozzle main body, a damper attached to the lower end of the nozzle main body and movable upward and downward, a spring suspending member fixedly provided within the main body at an upper portion thereof, a coiled spring suspended from the suspending member, a member connecting the lower end of the spring to free ends of the damper, and a resistant member secured to the connecting member and positioned below the coiled spring for acting against a downwardly flowing liquid. When a liquid is forced into the filling nozzle, the liquid pressure acting on the damper opens the damper against the force of the coiled spring, while the liquid pressure on the resistant member also acts to open the damper, opening the damper correspondingly to a greater extent. Consequently, the liquid flows out of the nozzle main body quickly without permitting formation of air bubbles due to agitation of the liquid that would occur at a low flow rate. Thus, the nozzle is adapted for a high-speed filling operation.
In recent years, however, there is a growing demand for a more efficient filling operation at a higher speed than is attainable by the above filling nozzle, so that it is desired to develop a filling nozzle which is operable at a higher speed than the proposed device.